My experiences are similar to Ken's. For dry rubs it is not worth the trouble and the flavor is not substantial enough to warrant the effort. I do like dried fruits (bananas and pineapple in particular) in some paste rubs but I do not use them in what most of us here would consider 'typical' barbecue. It is important to get the balance of wet, moist, and dry ingredients right if making a paste with dried fruits (one does not need them bone dry though). I'd recommend a grinder specifically for pastes as a mill or blender will gum up as Ken noted.
Very finely minced or powdered dried fruits are quite good as an element in stuffings (think stuffed pork chops, stuffed chicken breasts, et. al.).
Jams, jellies, reduced fruit juices, fruit syrups do have enough sugars in them to burn if too long in the heat. They make superb finishing glazes however. Most need no time in the cooker--the heat from the meat's surface alone is enough to seize and set them. To me, it is an excellent way to introduce fruit. A thin veneer of glaze will add fruit flavor and, done well, will not mask the rub, smoke or meat flavors but will act as one element of a layered flavor finish.